Place potatoes in a large saucepan and cover with water
Bring to a boil, reduce heat and cook until tender, about 20 minutes
Drain potatoes and return to stove-top to remove excess moisture
Add the ricotta, margarine, green onions, and garlic
With a masher, mash to desired chunky texture, adding enough milk to make creamy
Add in the Romano
Season to taste with salt and pepper